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Peatlands with very high C contents are generally considered a source of greenhouse gas (GHG) emissions. This research aimed to quantify the changes in peatland characteristics and GHG emission from the conversion of peatlands to agricultural areas. Height of water table, pH, electrical conductivity (EC), redox potential (Eh), organic carbon (OC), hot water-soluble C, total-N, the concentrations of NH4 +, and NO3 −, soluble-Al, soluble- Fe, and the emission of CH4, CO2 and N2O were quantified before and after land clearing of peats for agriculture. Results of study showed that pH, EC, OC contents, hot water-soluble-C, and total-N did not change after peatland clearing for agriculture. On the other hand, the concentrations of NH4 +, NO3 −, soluble-Al, soluble-Fe, redox potential and height of water table increased significantly after the peatland land clearing. Methane emissions from peatlands before peatland clearing were in the range of 0.13-0.22 mg C m−2 h−1 increased significantly to 0.14-0.31 mg C m−2 h−1 after the peatland clearing. The land clearing of peatlands for agricultural practices also caused increases in CO2 and NOx emissions by 85% and 76%, respectively. Changes in GGH emissions were not related to the changes in substrates quality of peats (OC contents, total-N and hot water- soluble-C). Results of the study indicate that increases in the GHG emission following the use of peatlands for agricultural areas are attributed to the changes in the peat characteristics.

One method of controlling disease that is environmentally friendly is the use of plant-based pesticides also known as botanical pesticides. The use of botanical pesticides has proven to be effective in controlling several species of pests and plant diseases, because they contains active secondary metabolite compounds. These compounds affect pathogenic microorganisms, so it is feared will also affect antagonistic microorganisms. This research will find out the impact of the application of several botanical pesticides on shallots to microbial biodiversity. The study was conducted in Peat-lands, at South Kalimantan. Microbial identification was carried out at the Phytopathology Laboratory and the Laboratory of Biological Control of the Department of Pests and Plant Diseases, Lambung Mangkurat University, Banjarbaru. The results showed that the application of plant-based pesticides from Kepayang fruit extract and Galam leaf extract had an influence in decreasing the population of microorganisms, respectively by 80.44% and 75.26%. Chirinyuh were increased the population by 36.60%, as well as the control treatment, the population of microorganisms increased by 17.77%. Meanwhile the application of synthetic pesticide Dhitane M-45 reduced the population of microorganisms by 95.73%. Types of microbes found in the soil and onion rhizosphere are Pseudomonas flourescens, Bacillus sp., Fusarium sp., Aspergillus sp., Curvularia sp., Scopulariopsis sp., Stachybotrys bisbyi, and Penicillium sp.

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The utilization of peatlands may decline the ecological functions of peatlands as carbon sink, water storage and biodiversity source. Therefore, different scientific approaches are required to increase peat productivity and inhibit decline in the ecological functions of peatlands. This article is aimed to provide information on researches that have been carried out in tropical peats in the South Kalimantan Province. The exploration and the potential utilization of microbes was reviewed from several studies conducted in the Desa Landasan Ulin Utara (LaURa), Kota Banjarbaru, South Kalimantan Province. Peat research carried out in the Desa LaURa during the dry season after peat fires in 2015 showed that microbial SRBM (mixture of N fixing, solubilizing P and cellulolytic microorganisms) from the modified recharge bio-pore system was able to improve the growth of roots, stems, and leaves, nutrient uptake, and increase production and biomass of soybean. In another research in 2018, the use of commercial biofertilizers containing Azotobacter sp and Lactobacillus sp applied to the LaURa peats significantly increased the total N and pH of peats but did not accelerate the decomposition of peat materials. In subsequent study on the exploration of nitrogen fixing microorganisms from the LaURa peats (sapric peats) which amounted to 10375-10500 cells g−1, the total N-fixing microbial population was correlated positively to the pH and EC of peats, and correlated negatively to the contents of peat organic C. Combining the results, the total N2 fixing microbial (NFM) population was significantly affected by organic C and peat EC (total NFM population = -154.052 + 33.126 pH + 607.117 EC, R2 = 51.63%). Results obtained from these studies demonstrated that the functional microbes of peatlands are able to maintain ecological functions of the peats.